Oil filter



March l2, 1940.

H. G. ElsLER OIL FILTER Filed June so, 1937 i can be readily forced Patented Mar. 12, 1940 UNiTsD Sfr-'ares l maar.;

The present invention relates in general to oil" filters, and more in particular to oil iilters for use in connection with internal combustion engines, especially the engines or motors of trucks and automobiles. The object of the invention' is to provide a more convenient, efl'icient,- and economical device of this character thanhas -been'known' heretofore. l, y -1 The various -features of the invention and its advantages will beipointed .out in detail in rthe course of the following description, in which reference is made to the laccompanying drawing.` Inthe drawing, f Fig. 1 is a'vertical section through the complete device, vexceptfthat the removable lter Canis shown only partly in section; .f Fig. 2 is a horizontal, section on the line-2---2,`

Fig..1; and z Fig. Bis apartial horizontal sectionon the same lineas Fig. 2, but looking in the opposite direction.

Referring to thedrawing, thereference character I indicates a cylindrical .casingor housing,

which is provided with a cup orgdome-shaped cover 2. These parts may be o cast-iron, or they may be drawn from sheet metal. As shown, the housing I has-a heavy rim Baround the top, in

which there is formed an internal annular channel to receive the gasket 1. The cover Z rests-on the gasket 'i and'is held in place by a stiff bail-like spring 8. The ends of the latter are positioned in grooves in the rim 6, While the central top portion normallyrests in a groovein the projection!) on the top oi the cover. This projection has rounded or sloping sides so that the spring member 8 gaged therefrom.

The bottom of the housing comprises an annular shelf or ledge 5, a wall portion 3 shaped like part of an inverted cone, and a at sloping wall portion 4. The shape of the bottom will -be understood clearly from Figs. 1 and 3: It will'be' seen that the modification of the cone-shaped bottom Wall 3 by the iiat portion 4 has the effect of widening the annular shelf 5 on one side to form an extension IILwhich is provided -with-a threaded opening for a coupling -II by means of which the inlet pipe I2 is connected.y `There is tending pin 34,having a pointedor.rounded1end1l Thepurpose of this pinwillbe explained later on;- The lter can is indicated byfthe reference subsequently. 1

into the groove and disenf. character I5,` and'will now be described. It lmay be similar to 'an ordinary tin can, but the top and bottom'jISand I1 are` perforated. Fig. 2 shows the perforations fin thefbottom of thelcan These perforations ofcourse provide for the' passage 'of oil through the can. Resting on thefbottm'ofythe" canon the'infside is a flat metal strip 24'; to 'which there isspot -Welded the nut 5;l 7The latter projects 'through a'central opening in the siredrlteringmateri'aL but I"prefer touse a mixat '28. "Thismixturezis granular. Above the ltering mixture and underneath the top AIIS vare two disks'2l2'andf23 of'lteriboard. The disks of filter board aboveandibelow .perform ay iiltering func tion and are also effective to retain therather line f granular iiltering` mixture.. Filter #board `of known character :may be used; suchlasjboard made jfroinf'many.layers of crepefpaper. As an additionalmeanslof-jpreventing escape ofthe ltering materialtheremay be a-disk 36 ofl paper or iinejwire gauge .inserted-*between the upper'iilterv board disk 2 2 and the top I6, as Will be explained The-filter. can orcartridge maybe further -described by-explainingthe method o f assembly of the complete cans, which of course areV received from the manuiaeturerqwith thetops unattached. In assembling a compl-ete can, the insideis .first given a coating of shellac, and then'thepieces of" iilter 'board itlY and f2-01and the metal strip 24 are placed on the-bottomand are covered by the diskZI. The strip 24 `must' .be so positioned that the small opening 32;'Fig; 2, coincideswith asimilar opening in the strip and to this end a template is'jprefe'rably"provided, having a crcularrecess the 'size' of the can',` a central l depressi'cnlarge enough to receive `the"nutt, and a shortstud or pinv Whch enters? the opening 32: Thistemplate maybe a `part of the machine 4by means of which the top is attached: In' practice the empty can may-be placed in position on the template with the pin labove Ireferred ,toventering ther opening 32. "Ihefstrip fi'is l.novvlplacediri position -so thatthe saidn pinzenters the-.openingnear one end of.l the strip, 4`with the'-other endfof .the strip adjacent .theside seam. as shown injFig. 2. rlhe bottom .of thecan'may. be attached .in manufacture ithroughxthe `aid of positioning means which insures;thedesiredpositional relation betweenfi'hea opening A3 2 in-.the'gbottom and the seam 35 of thegcanforthe openings maybekpunched.

after the bottom is attached. 'I'lie pieces of filter board I9 and 20 are now placed in position one on each side of the strip 24, and the disk 2| is then pressed into place. These pieces of lter board should t tightly into the bottom of the can.

A quantity of the ltering mixture is now placedin the can, and the latter is shaken or rolled so as the give part of the mixture an opportunity of adhering to the inside of the can due to the coating or^ shellac that has been applied. The can may be removed from the template for this purpose, and the tight fitting disk 2| `of i'ilter board will keep the strip 24 in place. y The adherent layer of filtering material is indicated at 29. iiltering mixture, after which the lter board disks 22 and 23 are pressed into place. The cover It may now be placed in position and is secured by the machine, which rolls the edge of the top and the flared-upper edge of the can together in the well known manner.

.These can tops are usually provided -with an annular gasket of paper or other material whichv and their edges. are heldby the shellac which ordinarily effectively seals the can. However, the operation-of making the rolled joint which attaches the top requires considerable force and may distort the shape :ofthe .can enough to break the seal between the side of the .can and the edge ofthe disks 22 and 23 at some point, and it is conceivable that a very fine crack might result which would permit small particles of filtering material to Work out. I prefer, therefore, to insert .the additional disk 36, as stated, although in most cases itwill be unnecessary.

The manner in which thelter can is assembled in the housing will now vbe described. The cover 2, it may be assumed, has not yet been placed in position. The gasket I8 is rst placed in the open housing, resting on the ledge 5, and the iilter can is lthenv inserted centrally in the housing. The can is then rotated if necessary until the pin 34, Fig. 3, enters the opening 32, Fig; 2, whereuponthe can will rest evenly on the gasket I8.` Pin 34 should be long enough to extend through the stripy 24, but should not perforatethe disk 2|.v This pin,. it will be seen, is a positioningV pin and serves to insure such location of the can Within the housing that the area 31 on the bottom of the can comes directly above the opening for the inlet pipe I2. 'Ihis prevents any` possibility of perforating the filter boards I9 or 28 and 2| by the pressure of the inowing oil, as` would be liable to occur if one of the large openings in the bottom should happen to come over the inlet opening, whichwould Aoften be the case if thevcan were located at random.

.The filter can having been placed in position, the bolt 21 is'inserted through the opening in the bottom of the housing and screwed into the nut 25. The bolt is then turned in tight, which draws the filter. can down-against the gasket I8, making' an oil tight connection at this point. The can is prevented from turning by the long .line of contact'fat the gasket I8, and strip 24 is The can is then replaced and filled with the 1 prevented from turning in the can by the pin 34 at one end and the seam 35 at the other. There is a gasket 26 under the head of the bolt 21, so as to seal the bottom' of the housing. The gasket 'I may now be placed in position, also the cover 2, and the latter is secured in place by the spring 8, as previously explained. The lter is now complete and ready for use.

The filter is installed in any suitable manner adjacent the motor with which it is to function. For instance, it may be located on the partition just in rear of the motor and underneath the hood, Where it is secured in place by a U bolt. A small block-oefv Wood may be provided to space the filterv away from the partition somewhat. This block should have a flat surface on the side 'next the partition and a semi-circular opening to receive the cylindrical housing I of the filter.

`After the block and ltei' are in position the `U bolt is passed through holes in the block and partitionwhich have been previously bored for this purpose, and the nuts are put on and tightened up. The U bolt is preferably located just beneath the rim IS and above the coupling I3. The filter .is thus held firmly in position.

The pipe I2 leads to the oil pressure line, to which'itis connected at any suitable point. It will be generally most convenient to connect to the branch line which extends to the pressure gauge on the dash or instrument panel. The pipe I4 extends to the crank-case.

The operation of the filter maynow be exs plained. When the motor is started up, the oil pump develops pressure in the lubricating syste'm and oil willflow through the inlet pipe I2 into the bottom of the housing I. The oil strikes the bottom of the filter can at the unperforated area 3'I and is diverted into the sludge sump 38, which is soon filled up. This sludge sump is the spacevvsurrounding the bolt2`| between the bottom of the housing and the bottom of the iltei` cani? As soon'as the sludge sump becomes filled,

annularspace or reservoir 39. Whenthe reser- Voir 39becomesfull up to the level of the open'- ing for the outlet pipe I4, it begins to drain off into the lcrank-case. The outlet pipe should be larger enough vto readily take care of all the oil that Acan passthrough the filter, so that the oil level outside the can Will not rise above the outlet opening.

When the filter can is new it will pass a considerable quantity of oil, in the neighborhood of one' quart or more per minute. This ratel of course decreases as the filtering material becomes clogged with dirt and other impurities that are extractedfin vthe operation of the filter. The coarser particles'of dirtmetal from the bearings, carbon, zetc. are stopped. at thel bottom of the lter can by theA filter boards and collect in the sump 3,8. vEiner-particles are stoppedy by the filtering mixture 28 in the interior ofthe can, which is also effective to remove other impurities suchras the .ifatty acids @which are gradually formed'by decomposition of the oil.v

The filtering. action will be readily understood, ini geheral,"butiit Will' 4be desirable to point out certa-in advantageous' features of applicants constructionl which' enhance its effectiveness as comfil LII)

vof other lters.

pared with known filter-s. yThe arrangement of housing and filter can whereby the sludge sump is formed between the bottom of the can andthe conical bottom of the housing is of primary iniportance in facilitating the deposit of the -larger impurities. The oil is delivered through the inlet I2 atconsiderable velocity but is deected by the bottom of the can and flows oi with greatly diminished velocity in a fan-shaped' stream directly across the sump, being again diverted upward through the cam at a plurality'of points distributed over the entire area of the can. This arrangement gives the maximum opportunity for deposit of the heavier impurities. Finer particles which are stopped by the lter board have a certainy tendency to adhere to the filter board and clog it up, but this .tendency is much reduced by the fact that the filter board is horizontal and theA particles are stopped by the under surface where they have much less chance of remaining than they do on the verticalA surfaces Further aid in4 preventing clogging is aorded by the action vof the oil flowing across the bottom of the can andby theshaking which occurs on the road, which tend to dislodge particles temporarily adherent to the lter board.

It should be noted at this point that the area presented bythe bottom of the can forthe intake of oil is riot limited to the area oi the perforations therein, but` is substantially 'the entire area ofI the bottom `of the can, from which of course must bel subtracted the 4ar'ea'lolo'cked off by the strip 24. This is because the tightening of the bolt 2l drawsthe bottom of the can down slightly, causing it to separate from the viilter boards lland 2li enough sothat the oil, after passing through the large holes inthe bottom I1,

has access to the whole under surface of the ilter board. The amount of .separation is usually very small and is not indicated in Fig. 1, -but it is suiicient for the purpose. At the top of the can there is no such effect, but it is not needed,*as the oil has been cleared of most of its impurities whenit reaches this point, and there is no tendency for the lter boards 22 and 23 to clog up.

The upward `llow of oil through the filtering mixture in the interior of the `canis uniform,

because the cross section of the material is the same from the bottom to the top. This tends'to prevent channeling, which is apt to start Sat any point of restricted cross section where 'the velocity or" flow is necessarily increased. Channeling alongthe sides of the can is prevented by the expedient already referred to, which vconsists in forming an adherent coating-of the ltering 'mixture on the inside of the can. This 'coating 'has a rough irregular outline -blen'dingwi'th the adjacent material packed intothe caniand entirely eliminates the natural tendency of the oil to follow up along the side of the can and form channels by-passing the filtering mixture.

After the oil passes out of the top of the filter v can it flows down over thesides ofthe can, as previously explained, to the reservoir 39, where kforeign particles such as might accidentally be on the outside of the can when installed have a chance to settle.

Filter cans as described herein are compara-` tively inexpensive, and it is contemplated that they should be replaced at rather frequent intervals. In the case of trucks which are serviced in accordance with a regular schedule the filter ing the oil.

service schedule is not observed, as would be the case with most private passenger cars, the filter may be readily inspected `bythe service station attendant at times when the oil is checked to ascertain ii any should be added. This isan impor-tant feature of the invention, not found iri kother filters, so far as known.

In order ,to inspect the lter and itsoperation the attendant merely has to detach the spring 8 and remove the ycover'2. This is done while the motor is running, and exposes Ithe whole' upper portion of the filter can soithat vthe flow of oil out of 'the top of the can and over the' sides thereof into-the reservoir39 can be `directly `cbserved. lf the oil `is passing throughiata good rate, and appears to be clean, the attendant will know that the filter is all right and will replace the cover. On the other hand, if` the flow of oilis scant or entirely stopped, or if `the oil appears dirty even though coming through at a good rate, the attendant will be advised that the llter can has become defective.

An insuilicient flow or stoppage will `of course be due to clogging of the filter which is bound to xoccur in time, while failure to clean the oil, which may occasionally 5 happen, may be due to any unforeseen or accidentaldeect. In "any event, if the filter can is notA functioning properly the fact is -at once evident.

In order to change the filter-can the attendant places some vconvenient receptacle under the filter, the motor having been stopped, and then unsc'rews rthe bolt 21. When the Abolt is removed in the sump and any remaining may 4be kreadily wiped out with a rag or ball of waste.l lTheoil lost in thus draining the lteris very small due to the design of thesump and reservoir, lwhich hold ay minimum quantity vof oil. A new I lter can is now inserted and -is secured lin place with the.

bolt 21, as previously explainediaiter` which the cover is replaced and the change is complete. The

time 'occupied is inconsiderable, being lscarcely more than is .required for checking and .replenish- The foregoing explanation of the manner of changing a filter `car-iwill malte evident an lirnportant lfeature of the filter,l which -consists in the fact that every time 'the attendant changes the lter can he is practically forcedto clean `out the sump also. Indeed, this isto alarge extent accomplished automaticallyby the drainage of the sump and reservoir. VTlieen'torced emptying of the sump is due'to the faict'that the -boltvwhich holds the lter can in place also serves to close thersump land thus the sump is -opened and. emptied every time the bolt is removed in changing the iilter can. This is a decided advantage or plugs, as the drainage` andfcleaning of such filters is difficult and is often neglected.`

Whilev I have describedin detail-a certain specific embodiment of my invention, it will be understood that this has been done merely to facilitate the explanation, and that the invention is not limited to the exact construction shown and described. Modifications maybemade to suit varying conditions, or for other reasons. I do not therefore wish to be restrictedv to the precise form and construction which has been illustrated and described, but desire to include and K. over other lters having separate drainage cocks have protected by Letters Patentlall forms. and modifications thereof that come within the scope of the appended claims.

I claim:

1. In an oil filter, a cylindrical housing having an opening at the top and an internal annular shoulder, a filter can partly enclosed in' said housing and having its lower rim resting on said shoulder, means for sealing the joint at said rim, including an element extending up through the bottom of said housing for drawing said rim against said shoulder, means for introducing oil into said housing beneath said can, the oil being under ,pressure and thevcan having perforations 'in the bottom and top to permit the oil to be forced through it lengthwise, ltering material in the can, an annular reservoir surrounding said can for receiving the oil fromthe top of the can, and means for continuously rdraining said reservoir at a point above the bottom thereof.

2. In an oil lter, a housing having an opening at the top and a depressed portion at the bottom to form a sump, a iilter can having its lower rim resting on a portion of the bottom of the housing surrounding said sump, said can projecting above the housing and cooperating with the wall of the housing to form a reservoir surrounding the lower portion of the can, means for introducing oil under pressure into said housing beneath the can, lling said sump, and means effective while the housing is open for sealing the sump from the reservoir at the point where the lower rim of the can engages the bottom of the housing, whereby oil is forced lengthwise through the can from bottom to top and overows into said reservoir, said last means including an element extending through the bottom of the housing for compressing the low rim of the can against the housing.

3. In an oil filter, a housing having a sump at the bottom thereof, said sump having a drainage opening, an annular ledge surrounding said sump, a lter can disposed in said housing with its lower rim resting on said ledge, a gasket in-- serted between said rim `and ledge, means passing through said drainage opening andeffective to close the same, and means cooperating with said closing means to compress the rim of said can against said gasket. i

4. In an oil lter, a housing having a depressed portion at the bottom forming asump, there being a drainage opening at the bottom ofsaid sump, a filter can having a nut secured to the bottom thereof, a ledge surrounding said sump on which the lower rim of the can is adapted to rest, and a bolt passing through said drainage opening and screwed into the said nut to clamp the can against said ledge and also functioning to close said drainage opening.

5. In an oil filter, a housing having a sump removal of said means to permit substitution of a new can effects automatic draining of the sump. 6. In-an oil filter, arhousing Ahaving an offset oil inlet at thev bottom thereof, a filter can adapted to bey disposed in said housing with the bottom of thecan adjacent said inlet, said can bottom being perforated except Afor av small area thereof removed from the center, and means for insuring correct'angular' adjustment of the can when' it is inserted in the housing so that the unperforated area of the bottom will be positioned directly above lsaid inlet; l 7. A lter can comprising a cylindrical body having aside seam and perforated top andbottorn` members, and securing means having a threaded; opening and including a member extending across the bottom of said can on the inside,l said' member having an edge portion abutting against said 'seam,.whereby the said seam tendsto'prevent said means from turning inthe can when a threaded member adapted to cooperatetherewith to hold the can in the filter in which it is to be used is screwed into said threaded opening.

8. A filter can comprising a cylindrical body and perforated. top and bottomv members, filtering material in said can,'a metal strip extending across the bottom of said can on the inside, and a nut welded to said strip and projecting through an opening in the bottom.

9. In an oil filter, a housing, a container disposed in said housing, a cover for said housing, ltering material in said container, a sump comprisingrthe space in the housing beneath the container, a reservoir comprising the space in the housing surrounding the container, sealing meansindependent of said cover for preventing thev direct passage of oil from said sump to said reservoir, said means including a gasket inserted between the lower rim of said container and an annular ledge surrounding said sump, together with an element extending from outside the housing through said sump into threaded engagement with the bottom of the container, means for introducing oil under pressure into said sump, whereby said oil is forced through said container and filtering material into said reservoir, and means for draining the oil from said reservoir to prevent its rise above a prede- HENRY G. EIsLER. 

